Question

我正在使用sql server 2008，其中我有一些麻烦我找不到一列

TblMaster 
  ID      Name      City     
  1       Hiren     Juanagadh
  2       Ashish    Gandhinagar
  2       Mayur     Ahmedabad
  3       Hitesh    Junagadh
  4       Nipun     Ahmedabad
  4       Vivek     Rajkot
  4       Samir     Surat
  5       Sagar     Vadodara

现在我想要Anoter列CountId所以我想要输出如下

TblMaster 
  ID      Name      City           CountId 
  1       Hiren     Juanagadh       0
  2       Ashish    Gandhinagar     2
  2       Mayur     Ahmedabad       2
  3       Hitesh    Junagadh        0
  4       Nipun     Ahmedabad       3
  4       Vivek     Rajkot          3
  4       Samir     Surat           3
  5       Sagar     Vadodara        0

表示如果Id列只有一个，则CountId = 0 如果Id列多于一个，则CountId = Idcolumn的计数

Answer 1

尝试此查询:::

select *,(case when (select count(id) from TblMaster )=1 
          then 0 else (select count(id) from TblMaster) end) as count 
from tblmaster

Answer 2

准备表

declare @T table ( 
           id int, 
           Name nvarchar(6), 
           City nvarchar(20))

insert @T values 
(  1 ,      'Hiren',     'Juanagadh'),
(  2 ,      'Ashish',    'Gandhinagar'),
(  2 ,      'Mayur',     'Ahmedabad'),
(  3 ,      'Hitesh',    'Junagadh'),
(  4 ,      'Nipun',     'Ahmedabad'),
(  4 ,      'Vivek',     'Rajkot'),
(  4 ,      'Samir',     'Surat'),
(  5 ,      'Sagar',     'Vadodara')

选择陈述

没有1-> 0校正

SELECT *, CountID  = count(*) over (Partition by ID)
from @T

使用1-> 0校正

select id, Name,City,CountID =  case when CountID = 1 then 0 else CountID end
 from (
SELECT *, CountID  = count(*) over (Partition by ID)
from @T )

RES

计算详细记录并在sql server的新列中显示

2 个答案: